1. Field of the Invention
The present invention relates to a drag adjusting mechanism. More particularly, the present invention relates to a drag adjusting mechanism for a dual bearing reel contrived to adjust a drag force of a drag mechanism serving to brake a rotation of a spool rotatably attached to a reel unit of the dual-bearing reel in a line reel-out direction.
2. Background Information
A dual-bearing reel has a drag mechanism serving to brake a rotation of a spool in a line reel-out direction and prevent breakage of a fishing line caused by abrupt, strong pulling. A lever drag type dual-bearing reel is known in which a drag mechanism is arranged surrounding a spool shaft. In order to adjust a drag force, a lever drag type drag mechanism employs a drag adjusting mechanism that includes a drag adjusting lever rotatably mounted onto a spool shaft.
A drag adjusting mechanism of a conventional lever drag dual-bearing reel has a drag adjusting lever and a cam mechanism contrived to convert rotation of the drag adjusting lever into an axial movement of a spool shaft. The cam mechanism has, for example, a cam receiving pin provided in the drag adjusting lever and a cam member having a cam surface configured to engage with the cam receiving pin. The cam member is supported on a reel unit such that it cannot rotate but can move freely in an axial direction. The cam member is contrived to act against the spool shaft so as to push a spool toward the drag mechanism, thereby pressing the spool against the drag mechanism. The cam surface of the cam member is formed along a circumferential direction of the cam member and configured such that its height along an axial direction of the spool shaft varies gradually.
With this kind of drag adjusting mechanism, when the drag adjusting lever is rotated, the cam mechanism causes the spool shaft to move in an axial direction and the spool moves in the same direction so as to press against the drag mechanism, thereby enabling the drag force to be adjusted.
With a lever drag type drag adjusting mechanism, the drag force can be adjusted from a drag released state in which the spool rotates freely to a maximum drag state by operating the drag adjusting lever. Consequently, if the drag adjusting lever is accidentally operated such that the drag adjusting mechanism enters the drag released state during fishing, then it will be possible for the spool to rotate abruptly in a line reel-out direction and cause the fishing line to become tangled on the spool due to backlash. Therefore, a conventional drag adjusting mechanism has a protruding portion configured such that it can contact an operating portion of the drag adjusting lever retractably provided on the reel unit in a position just in front of a drag release position (e.g., Japanese Laid-Open Patent Publication No. 2006-61012). With such a drag adjusting mechanism, when the drag adjusting lever contacts the protruding portion, the drag adjusting lever is prevented from rotating to the drag release position. A user can then move the drag adjusting lever to the drag release position by pressing the protruding portion and moving the drag adjusting lever past the protruding portion.
Recently, attempts are being made to reduce the size of lever drag type dual-bearing reels. When a protruding portion is used to restrict the rotation of the drag adjusting lever, it is necessary to provide a space for the protruding portion. Consequently, it is difficult to reduce the size of a dual-bearing reel that uses such a protruding portion. In order to reduce the size of a dual-bearing reel, it is feasible to use a technology in which a protrusion is provided on a cam surface of a cam mechanism and the protrusion serves to make it difficult for the drag adjusting lever to rotate to the drag release position (e.g., U.S. Pat. No. 6,402,073 B1 to Datcuk, Jr.).
In a conventional dual-bearing reel configured to restrict rotation of the drag adjusting lever with the cam surface, a protruding portion contrived to apply a minimal drag force is formed on the cam surface at a position just in front of the drag release position. The protruding portion has an apex, a first slanted surface that extends from the apex toward the drag release position, and a second slanted surface that extends from the apex in the opposite direction as the drag release position. The angle of the first slanted surface is larger than the angle of the second slanted surface.